Bone marrow transplants (BMTs) have saved thousands of lives since the first successful operation in 1968. The procedure became common in the late 1980s, and now 15,000-20,000 people a year receive BMTs, according to the Bone Marrow Transplant Information Network (BMT InfoNet).
"It's a fairly common procedure," says Susan Stewart, a BMT survivor and founder of BMT InfoNet. But she adds, "it's a procedure of last resort." That's because it's highly invasive for both the donor and recipient, though new technology may make it both easier and more effective. Stewart calls the operation "very uncomfortable," and says that the patient may have to remain in the hospital for more than six weeks following the procedure. Full recovery can take as long as a year.
Bone marrow is a soft, fatty tissue inside your bones that produces blood cells. Cancer, radiation therapy and blood diseases like aplastic anemia can all damage or destroy bone marrow. This can leave a patient with dangerously low levels of white blood cells, which are needed to fight infection. Immune deficiency diseases might also warrant a BMT.
Key to successful BMTs are finding a tissue match and resisting post-op infections. Usually marrow is taken from the hipbone of a close relative or the patient herself. (Healthy bone marrow can be taken from the patient prior to chemotherapy and stored for future use.) Advances in DNA technology, which helps doctors and patients find the closest tissue match, greatly contributed to the surge in successful BMTs. Still, 50 percent of recipients develop graft-versus-host (GVH) disease, in which the donated marrow starts attacking the body as if it were a foreign invader. (This is the opposite of the tissue rejection that occurs in most transplants, in which the body attacks the new organ.) GVH can be mild, or it can be deadly. Often, a patient must take immunosuppressants indefinitely to keep the new tissue from attacking the old, and this reduces the body's ability to fight infection.
Recent research suggests that blood cell transplants might be more effective than the traditional BMT. In both cases the idea is to replace hematopoetic stem cells, which are the cells that produce all types of blood cells (all blood cells "stem" from these few cells). The bone marrow houses the largest concentration of hematopoetic stem cells in the body, so you replace it hoping that the new cells will take over and rebuild the immune system. In a blood cell transplant, only the stem cells are injected in the body. This makes for an easier procedure for the donor, and it may produce better recovery rates. Stewart emphasizes that these findings are preliminary, and more research is necessary.